[c-nsp] slb ping probe

[Chris Knipe]

Hi All,

I'm hoping someone will be able to assist.  I'm currently exploring my
options in terms of using Cisco's SLB as an server load balance
instead of what we are currently doing.  The SLB itself, is working
absolutely flawlessly, and so far, saying that I am impressed is an
understatement.

I'm having an problem configuring probes however.  My configuration on
an 6506 (12.1(26)E5) is as follows:

ip slb probe PING ping
 interval 10
 faildetect 5
!
ip slb serverfarm FARM-SMTP
 nat server
 failaction purge
 probe PING
 !
 real 198.19.255.51
  weight 1
  inservice
 !
 real 198.19.255.52
  weight 1
  inservice
!
ip slb vserver VSERV-SMTP
 virtual 196.x.x.129 tcp smtp
 serverfarm FARM-SMTP
 inservice
!

On both the real servers, I can see that the ICMP ping request is
coming in from the switch, and I can see that both real servers send
replies to the switch.  However, the probe has been stuck in an
TESTING state now for a very long time and doesn't want to go
OPERATIONAL.

# sh ip slb probe detail
PING, ping, address = 0.0.0.0, interval = 10, faildetect = 5
  FARM-SMTP, type = server
    target = 196.43.208.129:25, real = 198.19.255.51:0, virtual =
196.43.208.129:25 TCP
      state = TESTING, status = 0, operation id = 9 Server NAT
      outages = 0, failures = 2213, successes = 0, tests = 2218
      current = never, cumulative = 00:00:00
    target = 196.43.208.129:25, real = 198.19.255.52:0, virtual =
196.43.208.129:25 TCP
      state = TESTING, status = 0, operation id = 10 Server NAT
      outages = 0, failures = 2213, successes = 0, tests = 2218
      current = never, cumulative = 00:00:00

tcpdump on one of the real servers:
08:25:59.155247 IP 198.19.255.33 > 198.19.255.51: ICMP echo request,
id 1802, seq 2264, length 44
08:25:59.156405 IP 198.19.255.51 > 198.19.255.33: ICMP echo reply, id
1802, seq 2264, length 44

Am I missing something?

-- 

Regards,
Chris Knipe